Ultrastructural observation of filtration membrane in cell-free and concentrated ascites reinfusion therapy for malignant ascites.

INTRODUCTION: Cell-free and concentrated ascites reinfusion therapy (CART) is used for the treatment of diuretic-resistant ascites. An increase in circuit pressure and clogging of the filtration membrane often occur in CART for malignant ascites. METHODS: To clarify the precise mechanism of filter clogging, we performed an ultrastructural observation study of the filtration membrane after the filtration of malignant ascites. RESULTS: The deposition on the filtration membrane was composed of blood cells, fibrin, or both. Cellular deposition was associated with a greater number of blood cells in the original ascites fluid. In contrast, fibrin deposition was associated with higher levels of interleukin-6, α1-antitrypsin, haptoglobin, and fibrinogen/fibrin degradation products. CONCLUSION: Our results suggest that the specific pathophysiologies of malignancy (such as inflammation or coagulation/fibrinolysis) and characteristics of malignant ascites (highly concentrated and cell-rich) are associated with clogging of the filtration membrane during CART.

[Cell-Free Ascites Reinfusion Therapy(CART)Modified by Keisuke Matsusaki(KM-CART)at Our Hospital].

Refractory ascites causes distress in patients with cancer. Cell-free and concentrated ascites reinfusion therapy(CART)is an option for the treatment of ascites. Conventional CART had drawbacks in terms of the volume of ascites it could treat and the complications it caused. As a result, a modified form of CART(KM-CART)was developed. The current study retrospectively examined the effectiveness and safety of KM-CART in patients with cancer. Nineteen patients with cancer underwent KMCART a total of 30 times between March 2017 and January 2018. The volume of the collected ascitic fluid was 7.0±2.6 L, and the albumin(Alb)concentration in the reinfused ascitic fluid was 52.6±31.4 g. Serum Alb level after KM-CART did not decrease from the pretreatment level, while serum creatinine(Cr)level decreased significantly. Abdominal girth and bilateral thigh circumference decreased significantly, and appetite improved. Adverse events were noted in the form of liver dysfunction( noted once)and postrenal failure(noted once), but both patients recovered with subsequent treatment. A decrease in the blood pressure was noted duringparacentesis and reinfusion of ascitic fluid, but blood pressure remained within an acceptable range, and a fever was not noted. KM-CART can treat a large volume of ascites and facilitates the treatment while causingfew adverse events. KM-CART is useful for ascites and greatly improves the quality of life(QOL)for patients with cancer.

[Cell-Free and Concentrated Ascites Reinfusion Therapy for Malignant Intractable Ascites from Colorectal Cancer].

Malignant intractable ascites worsens not only patient symptoms but also their daily activities. It often leads to a patient discontinuing or postponing chemotherapy. In the present study, we introduced cell-free and concentrated ascites reinfusion therapy(CART)for malignant intractable ascites from colorectal cancer. Six patients underwent 12 CART treatments using AHF-WMO as the ascites filterand AHF-UP as the concentrator(Asahi Kasei Medical Co., Ltd.)from January 2014 to January 2017. The patients included 2 men and 4 women aged 67-89 years. Primary locations were 3 rectums, 1 transverse colon, 1 descending colon, and 1 cecum. Five patients had peritoneal dissemination, and 1 patient had liver metastasis. All the patients were administrated diuretics, but they were all refractory to the treatment. The median punctured ascites volume was 3,850 mL, and the ascites reinfusion after CART was 485 mL, the median concentration was 7.5. Only one patient had a fever. Performance status(PS)improved significantly after the treatment, and appetite score also improved. One patient was fit to undergo chemotherapy after the treatment. In summary, we found that CART is a safe and acceptable procedure for malignant intractable ascites in colorectal cancer patients.

Identification and Characterization of Lineage(-)CD45(-)Sca-1(+) VSEL Phenotypic Cells Residing in Adult Mouse Bone Tissue.

Murine bone marrow (BM)-derived very small embryonic-like stem cells (BM VSELs), defined by a lineage-negative (Lin(-)), CD45-negative (CD45(-)), Sca-1-positive (Sca-1(+)) immunophenotype, were previously reported as postnatal pluripotent stem cells (SCs). We developed a highly efficient method for isolating Lin(-)CD45(-)Sca-1(+) small cells using enzymatic treatment of murine bone. We designated these cells as bone-derived VSELs (BD VSELs). The incidences of BM VSELs in the BM-derived nucleated cells and that of BD VSELs in bone-derived nucleated cells were 0.002% and 0.15%, respectively. These BD VSELs expressed a variety of hematopoietic stem cell (HSC), mesenchymal stem cell (MSC), and endothelial cell markers. The gene expression profile of the BD VSELs was clearly distinct from those of HSCs, MSCs, and ES cells. In the steady state, the BD VSELs proliferated slowly, however, the number of BD VSELs significantly increased in the bone after acute liver injury. Moreover, green fluorescent protein-mouse derived BD VSELs transplanted via tail vein injection after acute liver injury were detected in the liver parenchyma of recipient mice. Immunohistological analyses suggested that these BD VSELs might transdifferentiate into hepatocytes. This study demonstrated that the majority of the Lin(-)CD45(-)Sca-1(+) VSEL phenotypic cells reside in the bone rather than the BM. However, the immunophenotype and the gene expression profile of BD VSELs were clearly different from those of other types of SCs, including BM VSELs, MSCs, HSCs, and ES cells. Further studies will therefore be required to elucidate their cellular and/or SC characteristics and the potential relationship between BD VSELs and BM VSELs.

Mouse dental pulp stem cells support human umbilical cord blood-derived hematopoietic stem/progenitor cells in vitro.

It is well documented that specialized mesenchymal stem/stromal cells (MSCs) constitute the hematopoietic stem cell (HSC) niche in the bone marrow (BM), and these MSCs support/maintain the HSCs in an undifferentiated state. A number of studies have demonstrated that BM-derived MSCs (BM-MSCs) can support HSCs in vitro. However, it remains unclear whether nonhematopoietic tissue-derived MSC-like cells, such as dental pulp stem cells (DPSCs), have the ability to support HSCs. In this study, we prospectively isolated DPSCs from mouse mandibular incisors by fluorescence-activated cell sorting (FACS) using BM-MSC markers, such as PDGFRα and Sca-1. The PDGFRα and Sca-1 double-positive DPSCs and BM-MSCs showed similar morphologies and expression patterns of MSC markers. The ability of the DPSCs to support hematopoietic stem/progenitor cells (HSPCs) was then analyzed by an in vitro coculture system. Moreover, their HSC-supporting activity was evaluated by in vivo xenotransplantation assays using NOD/Shi-scid/IL-2Rγc(null) (NOG) mice. Interestingly, the DPSCs supported human cord blood (CB)-derived CD34-positive (CD34(+)), as well as CD34-negative (CD34(-)), HSCs. The supporting activities of DPSCs for human CB-derived CD34(+) and CD34(-) HSCs were comparable to those of BM-MSCs. The results of the present study demonstrated, for the first time, that prospectively isolated murine PDGFRα and Sca-1 double-positive DPSCs could support primitive human CD34(+) and CD34(-) HSCs in vitro.

Low level of c-kit expression marks deeply quiescent murine hematopoietic stem cells.

Although c-kit is expressed highly on murine hematopoietic stem cells (HSCs) and essential for bone marrow (BM) hematopoiesis, the significance of the high level of expression of c-kit on HSCs was not well determined. We show here that CD150(+) CD48(-) Lineage(-) Sca-1(+) c-kit(+) HSCs in adult BM are distributed within the range of roughly a 20-fold difference in the expression level of c-kit, and that c-kit density correlates with the cycling status of the HSC population. This predisposition is more evident in the BM of mice older than 30 weeks. The HSCs in G(0) phase express a lower level of c-kit both on the cell surface and inside the cells, which cannot be explained by ligand receptor binding and internalization. It is more likely that the low level of c-kit expression is a unique property of HSCs in G(0). Despite functional differences in the c-kit gradient, the HSCs are uniformly hypoxic and accessible to blood perfusion. Therefore, our data indicate the possibility that the hypoxic state of the HSCs is actively regulated, rather than them being passively hypoxic through a simple anatomical isolation from the circulation.

[A case of effective neoadjuvant chemoradiotherapy with capecitabine for locally advanced sigmoid colon cancer].

A 60-year-old man was hospitalized for urodynia. Clinical examinations demonstrated a locally advanced sigmoid colon cancer with direct extension to the bladder, rectum, and pelvic wall. We considered that curative resection was not possible and performed temporary colostomy for fecal diversion. After colostomy, he was treated with neoadjuvant chemoradiotherapy(NACRT)for down staging. The radiation therapy was delivered with 45 Gy(1. 8 Gy/fraction; 5 days/week×5 weeks), and the concurrent chemotherapy was performed with capecitabine(825mg/m2 twice daily on radiotherapy days). CT scan confirmed a dramatic response with downstaging of the tumor following NA-CRT(clinical response, PR in the RECIST criteria). Invasion of the tumor to pelvic wall disappeared on CT scan, and[18F]fluorodeoxyglucose positron emission tomography( FDG-PET)failed to demonstrate any distant metastasis. We considered that the tumor was hence resectable and performed total pelvic exenteration(TPE)1 month after NACRT. A pathological examination of surgical specimens confirmed a R0 resection. The patient made an unremarkable postoperative recovery. He went on to receive adjuvant capecitabine chemotherapy, completing four cycles. He remains well and disease-free 10 months following surgery. NACRT with capecitabine appears effective even for unresectable locally advanced sigmoid colon cancer.

Less morbidity after pancreaticoduodenectomy of patients with pancreatic cancer.

OBJECTIVES: The pancreaticoduodenectomy with extended resection has been frequently performed in patients with pancreatic cancer in Japan. One result of this additional surgical stress may be that postoperative complications in patients with pancreatic cancer are more frequent than in patients with periampullary cancer. METHODS: The 198 patients with pancreatic and periampullary cancer underwent pancreaticoduodenectomy. The operative mortality and morbidity between patients with pancreatic and periampullary cancer were compared, and the risk factors of postoperative complications and in-hospital death were determined. RESULTS: Patients with pancreatic and periampullary cancer made up 52% and 48% of total patients. The duration of surgery and volume of intraoperative blood loss were significantly higher in patients with pancreatic cancer than in patients with periampullary cancer. Additional organ resections were frequently performed in patients with pancreatic cancer. However, significantly lower morbidity rates were observed in patients with pancreatic cancer. Among all complications evaluated, pancreatic fistula and abdominal abscess were found less frequently in patients with pancreatic cancer. Logistic regression analyses showed a positive correlation between periampullary cancer and an increased risk of complications, pancreatic fistula, and abdominal abscess. The in-hospital mortality rate has significantly reduced since 2000. When pancreatic fistula was clinically diagnosed, we immediately started a closed lavage using continuous administration of natural saline at 1000 to 4000 mL/d, after exchange of a nasogastric tube drain. CONCLUSION: Pancreaticoduodenectomy for patients with pancreatic cancer can be a safe procedure in spite of surgical stress. Further surgical strategies will be needed to reduce postoperative complications, especially in patients with periampullary cancer.

Infrarenal abdominal aortic aneurysm complicated by persistent endotension after endovascular repair: report of a case.

Endoleak and endotension may prevent the successful exclusion of an aneurysm after endovascular aortic aneurysm repair (EVAR). The pressurization in the excluded aneurysm sac caused by endotension may lead to rupture of the aneurysm; however, the cause of endotension and its underlying mechanisms remain unclear. We report a case of infrarenal abdominal aortic aneurysm (AAA) complicated by persistent endotension after EVAR. Although no endoleaks were found on conventional double-phase computed tomographic scans, a thrombosed endoleak existed in the side branch and attachment site of the endograft. After treating the undetectable thrombosed endoleaks, physical examination revealed that the pressure of the excluded aneurysm had diminished, with shrinkage of the aneurysm. This case report suggests that a high-pressure undetectable type I or type II endoleak could be a major cause of endotension. Thus, postoperative evaluation of the attachment site of an endograft is important after EVAR.